Signal system



May 24, 1932. E. NEERUP 1,860,049

S IGNAL SYSTEM Filed Sept. 2'7. 1930 L QLB Patented May 24, 1932 EINAR NEERUP, 01 OAK PARK, ILLINOIS SIGNAL SYSTEM Application filed September 27, 1930. Serial N 0. 484,757.

:This invention relates to a signal system which may be used with particular advantage in the operation of an automobile. It is'associated with the motor lubricating systern, and includes in its assembly an indicator which may be located close to the operator.

A primary purpose of the present signal system is to convey a warning whenever there is a failure of oil pressure. For safe opera- 1 tion, a certain pressure should be maintained in the lubricating system of any motor. If the pressure, therefore, falls below a safety limit, or ceases altogether, the operator should be warned immediately so that the motor may be stopped to thereby avoid injury to its moving parts. The signal system of my invention is accordingly designed to afford an indication of any such changes in oil pressure conditions as call for an immediate shutting down of the power plant.

A preferred embodiment of my invention is shown in the accompanying drawings, in which Figure 1 -is a side elevation of an automobile engine showing in section the shroud and dash upon which are carried certain parts of the present invention;

Fig. 2 is an enlarged horizontal sectional view of the switch assembly taken as inclicated by the line 2 of Fig. 1;

Fig. 3 is an enlarged vertical sectional view taken as indicated by the line 3 of Fig. 1;

Fig. 4 is a perspective view of the supporting yoke;

Fig. 5 is and Fig. 6 is a diagrammatic view of the electrical system.

The switch assembly A includes a tubular housing having a vertically disposed cylindrical chamber 10 opening into an enlarged socket 11 at the bottom, as shown in Fig. 3, to which is applied a closure in the form of a cap 12 having a threaded connection with the tubular housing'with which it may be sealed as by a gasket 13.

The chamber 10 may be provided with a laterally disposed inlet 14 substantially in its center, and a lateral outlet 15 at its upper a perspective view ofthe piston;

end. The chamber may be further equipped in its upper region with a cross bolt 16 extending transversely through the housing, as shown in Fig. 2, the mountings for this bolt being insulated as by means of a pair of bushings 17. The bolt may be of the usual type having a head 18 at one end, its other end being threaded to receive the nuts 19 by which to connect with an electrical conductor 20. The insulating bushings may serve also to seal the openings through the housing forming thereby an oil tight connection for the bolt.

Slidably fitted Within the chamber is a plunger 21 having an axial opening which is outwardly flared as at 22 at its lower end, a socket 23 being provided at its upper end for the accommodation of a short spring 24. A constricted port 25 of a desired size is formed near the point of convergence for the flaring walls of the plunger opening. The chamber may further be provided with a support for the plunger of any desired construction, preferably by a yoke 26 made of spring wire having laterally extending feet 27 which fit in the socket 11. It will be seen that the portion of the chamber containing the yoke provides a settling pocket wherein particles of dirt may collect, and which may be readily cleaned by removing the cap 12.

The inlet 14 is connected as by copper tubing 28 to a convenient opening in the oil pump 29.

The outlet 15 may be joined to the oil return pipe 30 by a stem 31 which has threaded connection at 32 with the housing A, and a threaded connection at 33 with a boss 34 within the crank case.

The stem,

as shown, is provided with a shoulder 35 for securing the oil return pipe 30 to the crank case, and is further provided with an axial passage 36 which affords communication between the outlet 15 and the interior of the oil return pipe.

The indicating mechanism shown at B consists of a bracket 37 provided with a rearward extending socket 38 into which is fitted an electric bulb 39. The bracket may be secured to the instrument panel or other conveniently located place, so as to be in view of the operator.

The front of the socket ahead of the bulb may carry a colored glass which softens and tones the rays emanating from the bulb. To complete the electrical circuit a. conductor 41 connects one terminal of the bulb to a terminal block 42 which is supplied with current by a battery 43 through the ignition switch 44:.

The operation of the present signal system is as follows: With closing of the motor ignition switch 4% current is supplied to the terminal block 42, the conductor 41 and the bulb 39. Operation of the motor starts the oil pump 29 to force oil through the pipe 28 to the chamber 10 and through the constricted port 25. This orifice is of the proper size to set up a resistance to the flow of oil, such that the plunger is pushed up to about the position shown in dotted lines in Fig. 3, bringing the upper end of the spring 24 in contact with the cross bolt 16. A circuitis now completed through the bulb 39 since the plunger is grounded. This operation takes place with starting of the motor, and the bulb 39 remains lighted as long as the plunger is held in an upper position by the oil pressure from behind. If, for any reason, such as insufiicient or diluted oil, pump trouble, etc., the pressure should fall below the required amount requisite for the continued suspension of the plunger, the circuit through the conductor 20 will be broken, the light thereupon going off to indicate that the .oil system is not properly functioning. If upon leaving the car the bulb still emits light, this would indicate that the motor is still running. If the light flickers on and oil, it would suggest diluted oil, improper viscosity, or an overheated motor. The plunger may easily be replaced by one having a larger or smaller 1 orifice to assure proper operation of the indicator under diverse operating conditions.

I claim: 1. In a device of the kind described, the combination of a casing in which is a vertical cylindrical chamber having an inlet inter- J mediate its ends and an outlet at a somewhat higher point, a plunger formed with a constricted longitudinal passage slidable within the chamber and movable towards the upper end thereof in response to a pressure of liquidentering the inlet, stop means for limit- 2. In a device of the kind described, the

combination of a casing in which is a vertical cylindrical chamber havlng an inlet intermediate 1ts ends and an outlet at a somewhat ;higher point, a plunger slidable within the chamber, stop means for limiting downward movement of the plunger beyond a point substantially opposite the inlet, the plunger being provided with an axial passage which tapers toward an upper point where a constricted port is formed to create a resistance against the passage of liquid through the plunger, the upper end of the plunger being socketed to provide a seat, a coiled spring having one end received within the socket and sustained by the surrounding walls thereof, and an electrical contact projected into the chamber at a point above the spring when its supporting plunger is in lowermost position, the plunger when raised in response to a pressure of liquid entering the casing through the inlet presenting the upper spring end against the contact to complete an electrical circuit.

3. In a device of the kind described, the combination of a casing providing a vertical cylindrical chamber having intermediate its ends an inlet and an outlet at a point thereabove, the lower end of the chamber being open and enlarged interiorly, a plunger slidable within the casing, stop means for limiting downward movement of the plunger to a point substantially opposite to the inlet, the stop means comprising a U'shaped wire having its ends oppositely turned to provide feet which are accommodated Within the enlargement at the lower end of the chamber, a closure applied over the casing lower end and serving to confine the stop means in place, and an electrical contact projected into the casing at a point above the plunger adapted to be engaged thereby when the latter is raised in response to a pressure of liquid entering the casing through the inlet.

EINAR NEERUP. 

